The best way to update an Excel file to to use Excel itself via Windows automation and the Win32::OLE module. See the ActivePerl Winfaq12 for further details.

A less complete way is to use Spreadsheet::ParseExcel in combination with with Spreadsheet::WriteExcel (via Spreadsheet::ParseExcel::SaveParser). See the following WriteExcel FAQ.

For further information see davies' list of nodes and links related to Index of Spreadsheet FAQs.

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John.